(1) Field of the Invention
The present invention is directed to a drive system for a bicycle using a dual drive sprocket configuration with pedal board for providing additional support to the rider when powering the bicycle.
(2) Description of Related Art
The bicycle has been around as a means of transportation since the 19th century. Bicycles essentially work on a combination of gears and wheels with the riders providing necessary power for locomotion. Generally, two pedals are connected to a front gear that transfers rotational power from the rider to the rear hub of a rear wheel through a linkage such as a chain. Rotating the front gear causes the rear hub and ultimately the rear wheel to rotate providing locomotion. A front wheel is typically supported a fork connected to a frame. The front wheel also provides for steering by being attached to handlebars. A seat is typically included attached to the frame positioned generally between the front and rear wheels.
Typically, the rider of a bicycle is seated on the bicycle seat. However, there can be advantages to riding the bicycle in a standing position such as improved exercise, greater leverage for transferring power from the rider to the pedals and improved balance. U.S. Pat. No. 8,210,553 is one attempt to provide for a standing style bicycle and includes a chain installed between the two driving sprockets for rotating the two driving sprockets synchronously and a transmission sprocket driven by the sprockets to drive a rear chain to transfer power to the rear wheel. With the transmission of the two driving sprockets of this reference and the front chain, the first and second cranks can be rotated synchronously, so that when the left and right pedals are used, the pivot situated in the slide slots of the pedals will slide along the slide slots without hindering the stepping movement of the pedals. However, this configuration requires a complex arrangement between the front chains, transmission sprocket and rear chain to achieve smooth operation. Further, the transmission sprocket required that it have a sufficient height above the ground for clearance requiring a high center of gravity for the entire drive system.
United States Patent Application Publication 2007/0024019 is also an attempt to provide a standing step scooter. This reference describes a two and one half inch diameter back wheel gear, a drive chain attaching the small gear to the large gear, a left and right drive disk each having a shaft protruding outwardly from near the perimeter of the disk, a pair of step support bars including step platforms, each attached to the perimeter disk shaft, the end of each step support bar terminating in a roller wheel and corresponding tracks for each roller wheel to travel in.
U.S. Pat. No. 8,162,337 is also an attempt to provide a standing style bicycle and discloses self-propelled vehicle propelled by an elliptical drive train. This reference includes foot link assemblies that include a foot link, each with a foot platform, and a foot link coupler. At the rear of the elliptical bicycle, adjacent the rear wheel, are an adjustable stride length mechanism including adjustable crank arms, a drive sprocket, a crank arm bearing, a chain, a rear wheel sprocket, and a rear wheel hub. The drive system of the reference is generally disposed rearward and above the rear wheel.
It is an objective of the present invention to provide a frame for a standing type bicycle with platform pedals arranged in a manner to reduce the center of gravity for increased stability.
It is another object of the present invention to reduce the drive system profile by eliminating the need for multiple chains or complex crank arms and drive system.